JP5193548B2 - Permanent magnet rotating electric machine for fan drive of washing and drying machine - Google Patents

Description

  The present invention relates to a permanent magnet type rotating electrical machine employing a concentrated winding stator used for driving a fan of a washing / drying machine.

  An inverter-driven permanent magnet electric motor is employed as a rotating electric machine for driving a fan of a washing and drying machine. Recently, washing and drying machines have become mainstream, and in order to save energy, it is necessary to increase the air volume of the fan and shorten the drying time of the laundry. To increase the fan air volume, it is necessary to increase the speed of the permanent magnet motor. As a conventional example of this type of rotating electrical machine, as described in Japanese Patent Application Laid-Open No. 2005-94959, a rotor having a built-in two-pole permanent magnet is known.

JP 2005-94959 A

  However, in the thing of Unexamined-Japanese-Patent No. 2005-94959, the problem of the temperature rise at the time of light load is not disclosed. That is, the fan of the washing and drying machine has a wide operating range from low speed to high speed, and there is a problem that the temperature at a light load is abnormally increased.

  An object of the present invention is to provide a fan-driven permanent magnet type rotating electrical machine for a washing / drying machine that can cope with a low-speed to a high-speed rotation, and that can suppress a temperature rise particularly at a light load.

(1) In order to solve the above object, the present invention includes a stator having armature windings in a plurality of slots formed in a stator core, and a plurality of coils formed in a rotor core. A rotor in which a permanent magnet is placed in the permanent magnet insertion hole is rotatably supported through a predetermined gap on the inner periphery of the stator, and a cut surface is formed on the outer peripheral surface between the permanent magnets of the rotor core. When the opening degree of the rotor magnetic pole located above the permanent magnet is θ1, the opening degree of the teeth width is θ2, and the slot pitch of the slots is θ3, the configuration is such that the condition of θ2 ≦ θ1 ≦ θ3 is satisfied. together, and the ratio of (θ2 / θ3) to 55% or more, when the opening of the circumferentially extending pole pieces be in the tooth periphery was .theta.4, the ratio of (θ2 / θ4) to more than 64%, the magnetic poles An electromagnetic with a narrow magnetic pole opening between the first rotors laminated with magnetic steel sheets with a wide opening The 2nd rotor which laminated | stacked the steel plate is arrange | positioned so that it may be pinched | interposed in an axial direction, and the level | step difference formed in the axial direction by the circumferential direction edge part of the said 1st and 2nd rotor becomes V shape. The V-shaped step is configured to face the circumferential direction .
(2) The fan-driven permanent magnet type rotating electric machine for driving a fan of the washing / drying machine according to (1), wherein the axial length of the permanent magnet is shorter than the axial length of the rotor core.

  According to the embodiment of the present invention, when the opening degree of the rotor magnetic pole located above the permanent magnet is θ1, the opening degree of the teeth width is θ2, and the slot pitch of the slots is θ3, the condition of θ2 ≦ θ1 ≦ θ3 When the ratio (θ2 / θ3) is 55% or more and the opening degree of the pole piece extending in the circumferential direction on the inner peripheral side of the teeth is θ4, the ratio (θ2 / θ4) 64% or more, the leakage flux of the coil increases and the inductance increases, so the whisker current supplied from the inverter decreases, and the fan of the washing and drying machine can suppress the temperature rise at light load A permanent magnet rotating electric machine for driving can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
Examples of the present invention are shown below.

  FIG. 1 is an embodiment showing a radial sectional view of a permanent magnet type rotating electrical machine having a concentrated winding stator according to the present invention.

  FIG. 2 is an enlarged view of the stator of the permanent magnet type rotating electric machine of FIG.

  FIG. 3 is an enlarged view of the rotor of the permanent magnet type rotating electric machine of FIG.

  FIG. 4 is a perspective view of a rotor of the permanent magnet type rotating electric machine of FIG.

  Description will be made with reference to FIGS. In each figure, the common code | symbol shows the same thing. Here, a permanent magnet type rotating electrical machine having 6 poles and 9 slots is shown. 1A and 1C incorporate a rotor shown in FIG. 3A, and FIG. 1B shows a permanent magnet type rotating electrical machine incorporating the rotor shown in FIG. 3B. is there.

  A permanent magnet type rotating electrical machine 1 having a concentrated winding stator includes a stator 2 and a rotor 3. The stator 2 includes a stator core 6 including a tooth 4 and a core back 5, and concentrated armature windings 8 (three-phase windings) wound around the teeth 4 in slots 7 between the teeth 4. Line U-phase winding 8a, V-phase winding 8b, and W-phase winding 8c). Here, since the permanent magnet type rotating electrical machine 1 has 6 poles and 9 slots, the slot pitch is 40 degrees in mechanical angle and 120 degrees in electrical angle. As shown in FIG. 2, a magnetic pole piece 11 is provided on the inner peripheral side of the tooth 4 and extends in the circumferential direction on the inner peripheral surface of the tooth 4 facing the rotor 3. .

  Here, the opening at the point where the side surface of the tooth 4 and the top surface of the magnetic pole piece 11 intersect is the opening width θ2 of the tooth width, the slot pitch of the slot 7 is θ3, and the opening degree of the circumferential end face of the magnetic pole piece 11 is the magnetic pole. The opening degree of the piece is θ4.

  The rotor 3 includes a shaft hole 15 in which a permanent magnet 14 is accommodated in a single-letter permanent magnet insertion hole 13 formed in the rotor core 12 and is fitted to a shaft (not shown). Here, the axis extending in the direction of the magnetic pole center of the rotor 3 is d-axis. The axis extending in the direction between the magnetic poles separated by 90 ° in electrical angle from the magnetic pole center direction is defined as the q axis. By providing a concave portion 16 having a combination of two substantially V-shaped cuts in a straight line on the inter-pole (q-axis) side of the outer peripheral surface of the rotor core 12, the magnetic flux of the permanent magnet 14 is focused on the magnetic pole side. The rotor magnetic pole 17 that plays a role is formed. The rotor magnetic pole 17 has a rotor I in which a plurality of magnetic steel plates having a magnetic pole opening θ11 shown in FIG. 3A are stacked, and a magnetic pole opening θ12 narrower than the magnetic pole opening θ11 shown in FIG. There are two types with a rotor II in which a plurality of electromagnetic steel sheets are laminated. The opening degree of the rotor magnetic poles of the rotor I and the rotor II is collectively referred to as θ1. The rotor 3 shown in FIG. 4 has the rotor II arranged so as to be sandwiched between the rotors I. The rotor magnetic pole 17 is configured to be symmetric with respect to the magnetic pole center.

  In the present invention, a cut surface is formed on the outer peripheral surface between the permanent magnets of the rotor core, the opening degree of the rotor magnetic pole located above the permanent magnet is θ1, the opening degree of the teeth width is θ2, and the slot pitch of the slot Is set to satisfy the condition [θ2 ≦ θ1 ≦ θ3], the ratio (θ2 / θ3) is 55% or more, and the opening of the pole piece is θ4, the ratio (θ2 / θ4) is 64% or more.

  FIG. 5 shows a motor current waveform when the permanent magnet type rotating electric machine of FIG. FIG. 5 shows a comparison of motor current waveforms when the ratio (θ2 / θ3) described in JP-A-2005-94959 is 41.7%. From FIG. 5, the electric motor of the present invention has a small whisker current (maximum value of 1.67 A) while the electric motor of the present invention has a small whisker current (maximum value of 1.67 A). .35A)

  This is because the inverter power supply (not shown) uses AC100V as the main power supply, and the charging voltage of the capacitor reaches a maximum of 282.8V by the voltage doubler rectifier circuit, and this DC voltage is used to narrow down the voltage applied to the motor by PWM modulation. During a low-speed operation, such as a fan load, the load is light and the current for generating torque is small, but the whisker current increases because the DC voltage is high.

  Since the whisker current becomes an asynchronous magnetic field for the stator and the rotor, iron loss occurs in the stator core and the rotor core, causing a temperature increase.

  FIG. 6 is a temperature rise curve when the permanent magnet type rotating electric machine of FIG. 1 is operated. FIG. 6B shows the temperature rise of the armature winding during light load operation and rated operation when the ratio (θ2 / θ3) described in Japanese Patent Application Laid-Open No. 2005-94959 is 41.7%. It is a test result. From the figure, it can be estimated that the rise in temperature rises quickly during both light load operation and rated operation, and the iron loss is abnormally large. In addition, the temperature rise during light load operation was higher than that during rated operation, which was not normally considered. In contrast, FIG. 6A shows the condition when the opening of the rotor magnetic pole located above the permanent magnet of the present invention is θ1, the opening of the teeth width is θ2, and the slot pitch of the slots is θ3. It is configured to satisfy [θ2 ≦ θ1 ≦ θ3], and when the ratio (θ2 / θ3) is 55% or more and the opening of the pole piece is θ4, the ratio (θ2 / θ4) is 64% or more. It is the set temperature rise test result of the armature winding at the time of light load operation and rated operation. From the figure, it can be estimated that the rise in temperature rises slowly and the iron loss is small during light load operation and rated operation. In addition, the temperature rise during rated operation and light load operation was almost the same.

  The reason why the iron loss is reduced is that the opening degrees θ1, θ2, θ3, and θ4 are set to [θ2 ≦ θ1 ≦ θ3], the ratio (θ2 / θ3) is set to 55% or more, and the ratio (θ2 / θ4) is set to 64% or more. As a result, the slot becomes extremely narrow and high, so that the slot leakage magnetic flux increases, the slot leakage inductance of the armature winding increases, the rise of the current supplied from the inverter is delayed, and the whisker current is increased. This is because it becomes smaller.

  FIG. 7 is a schematic diagram showing a longitudinal section of a washing / drying machine equipped with a permanent magnet type rotating electrical machine having the concentrated winding stator of the present invention. In FIG. 7, reference numeral 20 denotes a rectangular cylindrical outer frame constituting the outer shell. The outer frame 20 is made of a chromium-free precoated steel plate.

  Reference numeral 21 denotes a washing and dewatering tub, which has a small hole 21a for water passage and ventilation on its peripheral wall, is provided with a fluid balancer 22 on its upper edge, and is provided with a stirring blade 23 on the inside of the bottom so as to be freely rotatable. . Reference numeral 24 denotes an outer tub that encloses the washing / dehydrating tub 21 and collects washing water and rinsing water. A drive unit 25 is attached to the outside of the bottom portion by a steel plate mounting base 26, and is attached to the four corners of the upper end of the outer frame 21. The outer tub 24 is uniformly suspended from four sides by the four anti-vibration support devices 27 that are locked, and is supported so as to be suspended from the center of the outer frame 21.

  The stirring blade 23 has a large diameter (the outer diameter is 90% or more of the inner diameter of the washing / dehydrating tub) that covers most of the bottom of the washing / dehydrating tub 21. Although the details of the stirring blade 23 are not shown, the central portion and the peripheral portion are high, and the space between them is low. The peripheral portion is curved upward so as to approach the outer periphery, and supports the laundry 28. Rotating.

  The driving device 25 includes a brushless DC motor 29, an electrically operated clutch mechanism 30, and a planetary gear speed reduction mechanism 31, and rotates the stirring blade 23 (stirring mode) while the washing and dewatering tub 21 is stationary, thereby washing and unloading. The water tank 21 and the stirring blade 23 are rotated in opposite directions (washing mode), respectively, and a selective drive function is provided to rotate the washing / dehydration tank 21 and the stirring blade 23 integrally (dehydration / drying mode).

  A drain port 24 b formed at the bottom of the outer tub 24 is connected to a drain hose 33 via a drain electromagnetic valve 32. The air trap 24 c is connected to the water level sensor 35 via the air tube 34. At the lower end edge of the outer frame 20, a base 37 made of synthetic resin with legs 36 attached to the four corners is attached.

  The top cover 39 formed with the outer garment insertion port 38 is fitted to the opening edge so as to cover the upper opening of the outer frame 20, is attached together with the front panel 40 and the back panel 41, and is attached to the outer frame 20 with screws.

  Although not shown in detail, the outer garment insertion port 38 formed on the top cover 39 is covered with an outer lid 43 attached to the top cover 39 by a hinge 42 so as to open in half (mountain fold). The inner garment insertion port 45 formed on the outer tub upper cover 44 attached to the upper end of 24 is configured to be freely opened and closed by an inner lid 47 attached to the outer tub upper cover 44 by a hinge 46.

  A front panel box 48 that is a front housing portion formed between the top cover 39 and the front panel 40 includes a power switch 49, an operation panel 50, an unbalance detection sensor 51, and a lid switch 52. The unbalance detection sensor 51 swings the washing / dehydrating tub 21 (outer tub 24) greatly beyond a predetermined value due to the unbalance of the laundry 28 in the washing / dehydrating tub 21 when the washing / dehydrating tub 21 is rotated. It is a sensor that detects The lid switch 52 detects opening / closing of the outer lid 43.

  The operation panel 50 is provided with setting buttons for determining a washing course, a drying course, a washing / drying course, and the like.

  A back panel box 53 formed between the top cover 39 and the back panel 41 incorporates washing water supply means and high-concentration detergent solution generation / supply means, which will be described later, and is located at the water level in the outer tub 24. A water level sensor 35 for generating a corresponding water level signal and a controller 54 are incorporated.

  The washing water supply means is constituted by a main water supply electromagnetic valve 58 having a water inlet side connected to a faucet connection port 55 and a water outlet side connected to a water injection port 57 via a detergent dissolution container 56.

  The high-concentration detergent liquid production / supply means supplies detergent-dissolved water to the detergent-dissolving container 56 via the auxiliary water supply electromagnetic valve 59 and stirs the powdered synthetic detergent put in the detergent-dissolving container 56 while stirring. Concentration detergent liquid is produced | generated, it is made to overflow from the detergent melt | dissolution container 56, diluting with further water supply, and to supply to the water inlet 57. The detergent dissolving container 56 is provided with a finishing agent charging chamber. By supplying water from the auxiliary water supply electromagnetic valve 60, the softening finishing agent charged in the detergent dissolving container 56 is overflowed from the finishing agent charging chamber. It is configured to supply to the water port 57.

  The hot air circulation drying means is a laundry that has entered from the suction port 61 formed so as to extend upward in a vertical state along the outer wall surface on the rear side of the outer tub 24 from the suction port 61 formed on the lower side wall of the outer tub 24. A water-cooled dehumidifying duct 62 that is a dehumidifying air passage section that dams water, a cooling water sprinkler 63 that is a water-cooled dehumidifying means that is located in the upper part of the water-cooled dehumidifying duct 62 and supplies cooling water to the duct, A descending air duct 64 that is a descending air duct portion that is folded back at a position higher than the water level of the outer tank 24 and extends vertically along the outer wall surface of the outer tank 24 toward the lower side of the outer tank 24, and the outer tank 24. A circulation fan 65 disposed in the lower space and sucking air from the descending air duct 64 into the suction port to generate circulating air, and the upper side of the circulation fan 65 along the outer wall surface of the outer tub 24 from the outlet. Perpendicular to direction A heating unit that heats the circulating air that is installed on the upper cover 44 attached to the upper end portion of the outer tub 24 and that is sent from the upward air passage duct 66. A heater (PTC heater) 67 is built in, and a blow-in port 68 through which heated circulating air is blown into the washing and dewatering tank 21 is provided.

  A yarn waste collecting means 69 is provided at the folded portion from the water-cooled dehumidifying duct 62 to the descending air duct 64. In addition, a humidity sensor 70 and a temperature sensor 71 are installed in the lower part of the descending air duct 64, and a second temperature sensor 72 is installed in the downstream air path of the heater 67 at the air inlet 68. Water is supplied to the cooling water sprinkling unit 63 from a cooling water spraying electromagnetic valve 73, and both are connected by a bellows hose 74.

  The water-cooled dehumidifying duct 62, the descending air duct 64, and the ascending air duct 66 constituting the circulation air path are arranged on the outer wall surface on the rear side of the outer tank 24 in the circumferential direction of the outer tank 24, and a part thereof is connected to the outer tank 24. The back cover 75 that is integrally molded and mounted and covers these outsides is configured to bulge outward and is screwed.

  This hot air circulation drying means drains the washing water in the outer tub 24 after washing, spins the washing and dewatering tub 21 at high speed and spins it, rotates it at high speed, rotates at low speed, or stirrer blades By operating the circulation fan 65 while reversing the direction 23 in the forward and reverse directions, the wet water in the outer tub 24 and the washing and dewatering tub 21 is sucked out from the suction port 61, and in the process of raising the inside of the water-cooled dehumidifying duct 62, It cools and dehumidifies with the cooling water supplied from 63 to the water-cooled dehumidifying duct 62. Thereafter, the dehumidified air is drawn down into the circulation fan 65 by lowering the descending air duct 64, and is sent from the circulation fan 65 through the ascending duct duct 66 and the heater 67 to the blowing port 68, and heated by the heater 67 to be washed and removed. Blow toward the center of the water tank 21. The circulating air blown into the washing / dehydrating tub 21 in this way touches the laundry 28 in the washing / dehydrating tub 21 to dry the laundry. Since this circulation fan 65 is a machine that handles water, the temperature increase rate becomes severe because a fully open type is adopted so that moisture does not enter.

  Consider a case where the permanent magnet type rotating electrical machine 1 of the present invention is applied to the circulation fan 65 of the washing and drying machine. The circulation fan 65 has a square load and has a wide operation range from the start of operation to the rated operation. For example, in the conventional case, when the rotational speed is reduced to operate with a ½ load, the whisker current is large even if the load current itself is small, and long-time operation cannot be performed because of the temperature rise of the electric element winding. On the other hand, even during rated operation, long-term operation cannot be performed due to the temperature rise of the armature winding.

  On the other hand, when the permanent magnet type rotating electrical machine of the present invention is used, the temperature rise of the armature winding is low regardless of whether it is operated at 1/2 load or rated operation. Since continuous operation of time is possible, the drying time of the laundry 28 can be shortened, which can contribute to energy saving.

  Further, in the present invention, the numerical value is limited to (θ2 / θ4)> 64% with respect to the opening θ2 of the teeth width and the opening θ4 of the magnetic pole piece, but this limit value is the armature winding during light load operation. The temperature rise is lower than that during rated operation, and at 100% of θ2 = θ4, there is no armature winding locking portion, and the upper limit is the armature winding fixing method or It is determined by the support method.

Further, in the present invention, the numerical value is limited to (θ2 / θ3)> 55% with respect to the opening θ2 of the tooth width and the slot pitch θ3, but this limit value does not increase the temperature of the armature winding during light load operation. It is defined by a structure that is lower than that at the time of rated operation, and the opening 18 of the slot disappears at 100% of θ2 = θ3, but is determined depending on the method of manufacturing a split core or the like.
According to the above configuration, the cut surface is formed on the outer peripheral surface between the permanent magnets of the rotor core, the opening degree of the rotor magnetic pole located above the permanent magnet is θ1, the opening degree of the teeth width is θ2, and the slot When the slot pitch is θ3, the condition [θ2 ≦ θ1 ≦ θ3] is satisfied, the ratio (θ2 / θ3) is 55% or more, and the opening of the pole piece is θ4. By setting (θ2 / θ4) to 64% or more, the leakage flux of the coil increases and the inductance increases, so the whisker current supplied from the inverter decreases, and the temperature rise during light load operation is suppressed. It is possible to provide a permanent magnet type rotating electric machine for driving a fan of a washing and drying machine.

  Next, a permanent magnet type rotating electrical machine according to a second embodiment of the present invention will be described with reference to FIG.

  FIG. 8 is a cross-sectional view of a rotor of a permanent magnet type rotating electrical machine according to the second embodiment of the present invention, and shows the XY cross-sectional direction of FIG.

  In FIG. 8, the rotor 3 has a permanent magnet 14 accommodated in a single-letter permanent magnet insertion hole 13 formed in the rotor core 12, but the axial length of the permanent magnet 14 is longer than the axial length of the rotor core 12. This is a shortened version.

  As a result, since the magnetic flux generated by the armature winding flows through the portion of the rotor core 12 where the permanent magnet 14 is not inserted, the inductance due to the armature reaction magnetic flux increases, the whisker current decreases, and the temperature during low-speed operation. It is possible to provide a fan-driven permanent magnet type rotating electrical machine for a washing / drying machine that can suppress the rise.

The radial direction sectional view of the permanent magnet type rotating electrical machine which has the concentrated winding stator by the present invention. The enlarged view of the stator of the permanent-magnet-type rotary electric machine of FIG. The enlarged view of the rotor of the permanent magnet type rotary electric machine of FIG. The perspective view of the rotor of the permanent magnet type rotary electric machine of FIG. The motor current waveform when the permanent magnet type rotating electrical machine of FIG. 1 is operated at a low speed. The temperature rise curve when driving the permanent magnet type rotating electric machine of FIG. The schematic diagram which shows the washing-drying machine which mounts the permanent magnet type rotary electric machine which has the concentrated winding stator of this invention longitudinally. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine by the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Permanent magnet type rotary electric machine 2 Stator 3 Rotor 4 Teeth 5 Core back 6 Stator core 7 Slot 8 Armature winding 9 Arc-shaped part 10 Beveling 11 Magnetic pole piece 12 Rotor core 13 Permanent magnet insertion hole 14 Permanent magnet 15 Shaft hole 16 Recess 17 Rotor magnetic pole 18 Slot opening 20 Outer frame 21 Washing and dewatering layer 22 Fluid balancer 23 Stirring blade 24 Outer tub 25 Drive device 26 Mounting base 27 Anti-vibration support device 28 Laundry 29 Brushless DC motor 30 Electric operation Clutch mechanism 31 Planetary gear reduction mechanism 32 Drain solenoid valve 33 Drain hose 34 Air tube 35 Water level sensor 36 Leg 37 Base 38 Outer clothing input port 39 Top cover 40 Front panel 41 Back panel 42, 46 Hinge 43 Outer cover 44 Outer tank upper cover 45 Inner clothing inlet 47 Inner lid 48 Front panel Box 49 Power switch 50 Operation panel 51 Unbalance detection sensor 52 Lid switch 53 Back panel box 54 Controller 55 Water faucet connection port 56 Detergent dissolving container 57 Water inlet 58 Main water supply solenoid valve 59, 60 Auxiliary water supply solenoid valve 61 Suction port 62 Water cooling Dehumidification duct 63 Cooling water sprinkling part 64 Down air duct 65 Circulating fan 66 Up air duct 67 Heater 68 Blowing port 69 Lint repair means 70 Humidity sensor 71 Temperature sensor 72 Second temperature sensor 73 Cooling water spray solenoid valve 74 Bellows hose 75 Back cover

Claims (2)

A rotor having a stator with armature windings in a plurality of slots formed in a stator core, and a permanent magnet inserted in a plurality of permanent magnet insertion holes formed in the rotor core. The rotor magnetic pole is rotatably supported on the inner periphery of the stator via a predetermined gap, and forms a cut surface on the outer peripheral surface between the permanent magnets of the rotor core, and is positioned on the upper portion of the permanent magnet. Is θ1, the teeth width opening of the stator core is θ2, and the slot pitch of a plurality of slots formed in the stator core is θ3, the condition of θ2 ≦ θ1 ≦ θ3 is satisfied. When the ratio (θ2 / θ3) is 55% or more and the opening of the pole piece extending in the circumferential direction on the inner peripheral side of the tooth is θ4, the ratio (θ2 / θ4) is Over 64% ,
Between the first rotor with laminated magnetic steel sheets with a wide magnetic pole opening, a second rotor with laminated magnetic steel sheets with a narrow magnetic pole opening is arranged so as to be sandwiched in the axial direction. The step formed in the axial direction by the circumferential end portion of the second rotor is V-shaped, and the laundry drying is characterized in that the V-shaped step is opposed to the circumferential direction. Permanent magnet type rotating electrical machine for fan drive.   The permanent magnet type rotating electrical machine for driving a fan of a washing and drying machine according to claim 1, wherein the axial length of the permanent magnet is shorter than the axial length of the rotor core.

Images